Federal agents have been accused of carrying out an improper search of documents contained on the computer of a former Reuters journalist who has been charged with conspiring with hackers to deface the website of the Los Angeles Times.

Matthew Keys, 26, has been indicted for providing a username and password to the hacker group Anonymous that allowed it to hack into the Los Angeles Times website and alter a headline.

At the US district court in Sacramento on Wednesday, an attorney for Keys, Jay Leiderman, said federal agents carried out a trawl of files on Keys's computer in 2012 that was not allowed under their search warrant. He asked that information taken from the computer be suppressed by the court."The warrant did not give the power to rummage through the journalist's files," Leiderman said, adding "there is no indication of why all this information needed to be seized".The computer in question was used by Keys to send files regarding his own case to another journalist who was writing a book about Anonymous in 2012. It is not clear what the prosecution intends to do with the information agents found during the search or if any of it will be used in an upcoming trial.The prosecution argued that agents carried out a broad search of the computer because they were concerned relevant files could have been moved or hidden. They further argued that child pornography cases, in which entire hard drives are seized and used as evidence, set a precedent for such indiscriminate searches.Leiderman responded by saying, as a journalist, Keys would be unlikely to move or tamper with files relating to an ongoing story and rejected the idea that child pornography cases are analogous to this case.Judge Kimberly Mueller is expected to give her decision on the legality of the search on 26 February.The case against Keys has caused a stir in the online media community, where many are concerned he is the victim of over-stringent action by law enforcement. He faces three charges in total under the 1984 Computer Fraud and Abuse Act. Each charge carries a potential fine of $250,000 and potential jail terms of five years on one count and 10 on each of the other two.Supporters of Keys point out that his actions caused little disruption to the LA Times. The hackers used the password to change one headline from "Pressure Builds in House to Pass Tax-Cuts" to "Pressure Builds in House to Elect CHIPPY 1337." CHIPPY 1337 is a reference to another hacking group.The headline was quickly amended and the password changed to avoid further breaches. The company that owns the LA Times spent $5,000 updating security measures to avoid a recurrence, according to the indictment.The alleged offences occurred in 2010 when Keys was working for KTXL Fox 40, a Sacramento-based television station owned by the Tribune Company, which also owns the LA Times.Keys later moved to Reuters where he worked as a social media editor before being put on paid leave once the charges were brought against him. He was later dismissed. He will appear in court again on 26 February when Mueller will giver her decision on the application to suppress.